Two submersibles, one red and one blue, started rising toward the surface at the same time. They each rose at a constant speed. The red submersible started rising from an altitude of $80$ meters below the surface. After $30$ seconds, it was $60$ meters below the surface. The altitude (in meters relative to the surface) of the blue submersible as a function of time (in seconds) is given by the following function: $\qquad A(t) =-90+0.6t$ **Which submersible started rising from a higher altitude?** [[☃ radio 1]] **Which submersible rose faster?** [[☃ radio 2]]